Started Last Night / Highly Anxious Today

Hello friends, I started on .50 last night. This morning I woke up to extreme jitters and jaw clenching which made me highly anxious. My intrusive thoughts got the best of me and I started thinking what if I go into a panic or go crazy because of the meds and i almost worked myself up into a panic attack. The jitters went away but the intrusive thoughts seem extra hardcore and plaguing. I have Xanax I can take to chill out but hate having to do that… is this a normal reaction? I was in them years ago and don’t remember it being this hard getting on them. Any words to give me peace?